Describes How To Use Your Ni - National Instruments NI 4350 User Manual

NI 4350 Operation
Warming up Your NI 4350 Instrument
Choosing a Measurement Mode
Note:
Choosing a Range
© National Instruments Corporation
This chapter describes how to use your NI 4350 instrument and includes
operation tips on taking measurements with temperature sensors such as
thermocouples, RTDs, and thermistors, as well as measuring voltages
and resistances.
To minimize the effects of thermal drift and to ensure the specified
accuracy, allow the NI 4350 instrument to warm up for at least
10 minutes after power-up before taking measurements. To maximize
the relative accuracy of measurements, take all measurements after your
NI 4350 instrument warms up for about 30 minutes.
Each analog input channel can be configured in two possible
measurement modes — the volts mode or the 4-wire ohms mode. Use the
volts mode for thermocouple and voltage measurements and the 4-wire
ohms mode for RTD, thermistor, and resistance measurements using the
built-in current source to provide excitation for your resistive sensors.
In the 4-wire ohms mode, the software will return the resistance value
by dividing the voltage measured by the value of the current source
stored onboard.
VirtualBench, the NI435X instrument driver, and the DAQ Channel
Wizard select the measurement mode automatically, depending on the
sensor type you specify.
The volts mode has six bipolar input ranges: ±625 mV, ±1.25 V,
±2.5 V, ±3.75 V, ±7.5 V, and ±15 V.
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Chapter
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NI 4350 User Manual